#集合
s = {1,2,3}
print(type(s))

s.add(999)
print(s)

s.add((1,3,5))
print(s)

s.update((1,3,5))
print(s)

s.update((1,2,3,4,5,6,7,8,9,10))
print(s)

s.remove(999)
print(s)

# s.remove(11)
# print(s)

s.discard(2)
print(s)

print(s.pop())


print(9 in s)
print(9 not in s)